Process for manufacture of a flexible package

ABSTRACT

A process for the manufacture of flexible packages. The process may utilize a continuous flexible wall material sequentially attached to a reinforcing member. The process may have the ability to form multiple packages in a single moment.

FIELD OF THE INVENTION

This invention relates to the process for the manufacture of flexible packages. The packages may be suitable for a variety of applications. The process may utilize a continuous flexible wall material sequentially attached to a reinforcing member. The process may have the ability to produce multiple flexible packages in a continuous in-line production process.

BACKGROUND OF THE INVENTION

A wide variety of packages for articles of all different types are known in the art. Many of the features of such packages are dictated or influenced by the products or items they are designed to hold or carry or the uses to which they are expected to be put. For example, moisture containing cleansing articles such as wet wipes (such as adult toilet wipes, cleaning wipes, and wet baby wipes for the hands, face, or diaper change wiping) are often packaged in either hard plastic “tubs” or smaller, often flexible packages for more portable use. In the example of wet wipes, or other moisture containing articles, the articles may be dispensed with one hand (for example when holding a baby with the other hand). In such a case, it may be desirable to be able to open the package, dispense an article, and close the package with a single hand. Other possible desired attributes of a package for articles such as moisture containing cleansing articles are that it be flexible, compact, and remain open or closed without further action by the user. Of course some or all of these attributes may be desired for packages for uses other than containing moisture containing cleansing articles. These attributes and others may be desired in any combination. Packages having some or all of these attributes (and others not necessarily included on this list) may be desired for a wide variety of applications.

In particular, there may be a desire to have flexible packages which can store articles and be opened and closed with a single hand. It may be desired that the package remains open once opened by a user without further application of force and that when closed by a user, the package remains closed. It may also be desired that such packages be re-usable if desired, such as by refilling them in whole or in part with additional articles such as moisture containing cleansing implements. It may be desirable to formulate a process which can produce flexible packages which can store articles and be opened and closed with a single hand.

Processes known and used to assemble packages with the desired attributes generally do not complete the package assembly as a single process. Known processes may require some amount of human manipulation during the process to complete assembly of the packages.

Known processes which utilize some degree of human manipulation to assemble single discrete packages may have limited throughput of completed packages. There may also be lower reliability of the process if human manipulation is required or if each package is handled discretely by equipment. High costs associated with package assembly may result from processes which rely on human manipulation or single discrete package assembly.

It may be beneficial to provide new processes which can manufacture flexible packages that can reduce or eliminate the need for human manipulation of the packages. It may also be beneficial to provide new processes in which an in-line continuous flexible wall material is utilized rather than discrete pieces of flexible wall material. The use of the continuous flexible wall material can provide greater handling capability as well as greater control capability. Both of these capabilities may result in higher processing speed and less variance in the resulting flexible packages. It may further be beneficial to provide new processes that open up opportunities for producing new packages which allow for an increased throughput and generate multiple packages. It may be beneficial to provide new processes that reduce or eliminate human error and allow for an increase in the quality of the package that is assembled. It may further be beneficial to provide new processes at reduced manufacturing cost.

SUMMARY OF THE INVENTION

The present invention relates to a process for making a flexible package comprising the steps of providing a continuous flexible wall material, providing a reinforcing member comprising a perimeter of an opening, attaching the flexible wall material to a first portion of the reinforcing member perimeter to provide a composite structure comprising an attached first portion and an unattached second portion, cutting the flexible wall material at points beyond the reinforcing member to produce package pre-forms, and attaching the remainder of the flexible wall material to the remainder of the reinforcing member perimeter to fully form the flexible package.

In certain embodiments of the present invention, the reinforcing member may be in the shape of a square, rectangle, circle, ellipse, polygon or oval.

In certain embodiments, the reinforcing member may comprise a leading edge, a trailing edge, and opposed side edges. In such embodiments, the flexible wall material may be first attached to the opposed side edges. The flexible wall material may then be attached to the leading and trailing edges.

In certain embodiments of the present invention, a package pre-form seal may be created at a location external to the perimeter of the reinforcing member. The package pre-form seal may then be cut at a location intermediate to the edges of the package pre-form seal to create discrete package pre-forms.

In certain embodiments of the present invention, the process may comprise a further step of forming a gusset in the bottom of the flexible package.

In certain embodiments of the present invention, the process for making a flexible package may comprise the steps of providing a continuous flexible wall material, providing a reinforcing member comprising a perimeter, attaching the flexible wall material to a portion of the reinforcing member perimeter, closing the reinforcing member, forming a package pre-form seal outboard of the perimeter of the reinforcing member, cutting along a line at a position intermediary to the seal edges to create discrete segments of flexible packages, opening the reinforcing member and attaching the flexible wall material to the remaining portion of the reinforcing member perimeter.

In certain embodiments of the present invention, attachment of the flexible wall material to a portion of the reinforcing member perimeter may occur while the reinforcing member is in a closed or sufficiently closed configuration.

In other embodiments of the present invention, attachment of the flexible wall material to a portion of the reinforcing member perimeter may occur while the reinforcing member is in an open or sufficiently open configuration.

In certain embodiments of the present invention, the process for making a flexible package may comprise the steps of providing a continuous flexible wall material, providing a reinforcing member comprising a perimeter, attaching the flexible wall material to a portion of the reinforcing member perimeter, closing the reinforcing member, forming a pre-form seal outboard of the perimeter of the reinforcing member, opening the reinforcing member and attaching the flexible wall material to the remaining portion of the reinforcing member perimeter, and cutting along a line at a position intermediate to the seal edges to create discrete packages.

The present invention may also relate to the production of multiple package pre-forms continuously attached to each other prior to separation into discrete packages.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as forming the present invention, it is believed that the invention will be better understood from the following and foregoing description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan view of an exemplary flexible package, which can be produced by the production line of the present invention.

FIG. 2 is a plan view of exemplary reinforcing member shapes.

FIG. 3 is a plan view of multiple composite structures and package pre-forms made according to the present invention.

FIG. 4 is a schematic diagram of one embodiment of the production line of the present invention in which the reinforcing member experiences both closed and open configurations.

FIG. 5 is a schematic diagram of one embodiment of the production line of the present invention for producing flexible packages in which the reinforcing member remains in an open configuration.

FIG. 6 is a schematic diagram of one embodiment of the production line of the present invention for producing flexible packages in which the reinforcing member is in a partially closed configuration.

FIG. 7 is a schematic diagram of one embodiment of the production line of the present invention for producing flexible packages with an optional gusset.

DETAILED DESCRIPTION OF THE INVENTION

The present invention may reduce or eliminate the need for discrete pieces of flexible wall material and human manipulation. The present invention can combine the use of a continuous flexible wall material with a fully automated system into a continuous process for assembling flexible packages. In one embodiment, the package can be opened or closed with one hand.

Terminology

The term “continuous process” refers herein to an in-line production process that may produce multiple packages without stopping. The continuous process may comprise providing a plurality of reinforcing members, providing a supply of flexible wall material and aligning the reinforcing members and the flexible wall material in a spaced-apart relationship on an assembly line. The reinforcing members and flexible wall material may be attached to form composite structures, package pre-forms and further processed into packages.

The term “continuous flexible wall material” refers herein to a component of a package made according to the process of the present invention that is sufficiently long so as to produce multiple packages from that component.

The term “material” refers herein to include either a natural or synthetic material or any combination thereof, including films, film laminates, non-woven laminates, sponges, non-woven webs, woven webs, knitted fabrics, foams, natural materials, and any combination thereof, or dry lap materials including wood pulp, and the like, having a single layer or multiple layers.

The term “non-woven fabric” or “non-woven material” or “non-woven web” or “non-woven” refers herein to a material made from continuous filaments and/or discontinuous fibers, without weaving or knitting by processes such as spun-bonding and melt-blowing. The non-woven material can comprise one or more layers of the non-woven material, wherein each layer can include continuous filaments or discontinuous fibers.

The term “foam” refers herein to any material comprising a solid, liquid crystalline, or liquid continuous phase and a gaseous dispersed phase. Because of the dispersed gaseous phase, foam has a density less than the density of the continuous phase.

The term “film” refers herein to any polymeric sheet made by a process such as, but not limited to, extrusion of a polymeric material through a narrow slot of a die. The polymeric sheet can optionally be impervious to a liquid and pervious to an air vapor.

The term “polymer” or “polymeric” refers herein to thermosetting and/or thermoplastic compositions, including but not limited to, polyolefins, including polyethylene, polypropylene, linear low density polyethylene, low density polyethylene, low density polypropylene, high density polyethylene, high density polypropylene, polyesters, polyamides, polyacetals, polyethers, poly (meth) acrylates, thermoplastic elastomers, styrenic block copolymers, metallocene-catalyzed polyolefins, polyether amides, polyurethanes, polyvinylchloride, superabsorbent materials, rayon, ethylene vinyl acetate, ethylene vinyl alcohol, and blends and copolymers, filled polymers, biconstituent or bicomponent mixtures thereof and combinations thereof. The polymeric material can also include various pigments to provide desired colors and/or visual effects and other components such as antioxidants, fillers (such as magnetoplumbite-structure ferrite particles), processing aids and the like.

A “natural material” means herein a material derived from plants, animals, insects or byproducts of plants, animals, and insects. Non-limiting examples of natural materials include cellulosic fibers, cotton fibers, keratin fibers, silk fibers and the like. Non-limiting examples of cellulosic fibers include wood pulp fibers, hemp fibers, jute fibers, and the like. Non-limiting examples of keratin fibers include wool fibers, camel hair fibers and the like.

The term “attach” herein refers to a component of a flexible package is at least partially secured directly or indirectly (by one or more intermediate members) to another component of the flexible package. Attachment may be relatively continuous or intermittent. Relatively continuous attachment may imply that the components are bonded together over substantially all of one or more dimensions of a common interface between the components. Intermittent attachment may imply that the components are bonded together with one or more individual, discrete bonds that are not continuous or bond patterns having open areas free of bonds. Attachment may be conducted by a variety of methods well known in the art such as adhesive bonding, thermal bonding, mechanical bonding, ultrasonic bonding, heat bonding, pressure bonding, stitching, induction bonding, RF bonding, microwave bonding, laser bonding, and the like. If the attachment is performed by an adhesive applicator, the adhesive applicator may apply an effective amount of adhesive so as to make the attachment.

The term “flexible” or “flexible” means herein that the material out of which the package walls are constructed will tend to conform or deform in the presence of externally applied forces. As measured under the Stiffness of Fabric test, the flexible wall material may have a peak load of less than about 1000 g_(f).

The term “reinforcing member” means herein a component of the package which offers more resistance to bending or deformation than the flexible packaging material as a whole.

Exemplary Flexible Package

The following description describes, in detail, features of flexible packages which may be produced according to the present invention. It should be noted that the design elements and attributes described herein are exemplary and the scope of the invention is determined solely by the appended claims. One example of a flexible package that can be produced by the process of the present invention is illustrated in FIG. 1. FIG. 1 shows a flexible package 20 made according to the present invention in an open configuration.

The package 20 may comprise as its basic components a flexible wall material 40 and a reinforcing member 50. These basic components may provide primary functions of a package for a wide variety of moisture containing articles, and also normally define the size, shape and the perimeter of a particular package. These basic components may also be combined to produce a flexible package which can store articles (not shown). Further the package 20 may be opened and closed with a single hand. As shown in FIG. 1, the basic arrangement of the flexible wall material 40 of the package 20 may be such that the flexible wall material 40 surrounds the articles to be contained and dispensed. In this exemplary configuration, the flexible wall material 40 may define a flexible package having four side walls, such as side walls 80 and 81, bottom wall 82, and an opening 70. The package 20 may also comprise an end seal 30 formed according to the present invention. The package 20 shown in FIG. 1 may also comprise a reinforcing member 50 defining a perimeter of the opening 70 of the package 20.

The bottom wall 82 of the package 20 may be formed by a single sheet of continuous flexible wall material 40 or by multiple sheets of flexible wall material 40. A single sheet of flexible wall material 40 inserted into a production line of the present invention may be folded or otherwise configured to provide two opposing panels 42 and 44 (shown in FIG. 5). The opposing panels 42 and 44 may be attached to the reinforcing member 50 to form a continuous bottom wall 82 of a package 20 and two opposing side walls (such as side wall 81). In another embodiment, separate opposing sheets of flexible wall material 40 may also be used to form a bottom wall 82. In this embodiment, the separate, opposing sheets of flexible wall material 40 may each have an upper end (not shown) and a distal end (not shown). The upper ends of the sheets of flexible wall material 40 may be attached to opposing sides of the reinforcing member 50. The free distal ends of the sheets may be attached together to provide a sealed bottom wall 82.

The package 20 may take on various overall shapes. As exemplified in FIG. 1, the package 20 may be in a substantially parallelepiped configuration. Alternative shapes of the package 20 may also include, but are not limited to, tubular, square, V-shape, U-shape, gusseted, and non-gusseted. The package 20 may contain a reinforcing member 50 comprising a perimeter. The perimeter may initially serve as the border of the reinforcing member 50 and provide a structure on which to attach the flexible wall material 40. The perimeter may be discernible as any pathway or portion along the reinforcing member 50 that may form a closed loop. Once the package 20 of the current invention has been produced, the perimeter of the reinforcing member 50 may also define the opening 70 of the package 20. The reinforcing member 50 may comprise hinge elements 15 so as to enable the package 20 to open and close.

As shown in FIG. 1 the overall dimensions of package 20 may be selected to result in a configuration useful for containing various articles. For example, in the configuration shown in FIG. 1, the package 20 may have an overall length dimension L of from about 70 to about 600 mm. In another embodiment, the overall length dimension L may be from about 70 mm to about 450 mm and from about 70 mm to about 300 mm in yet another embodiment. Similarly, the width dimension W may be from about 30 mm to about 400 mm. In yet another embodiment, the width dimension W may be from about 30 mm to about 300 mm and may be from about 30 mm to about 200 mm in yet another embodiment. The height dimension of the package 20 in the closed configuration H_(c) may be from about 30 mm to about 300 mm. In yet another embodiment, the height dimension in the closed configuration may be from about 30 mm to about 750 mm and from about 30 mm to about 1450 mm. The height of the package 20 when in the open configuration H_(o) may be greater than the height of the package 20 when in the closed configuration H_(c). The height dimension of the package 20 in the open configuration H_(o) may be from about 40 mm to about 400 mm. In another embodiment, the height dimension of the package in an open configuration may be from about 40 mm to about 800 mm and from about 40 mm to about 1500 mm in yet another embodiment.

As exemplified in FIG. 2, the shape of the reinforcing member 50 may be in the shape of, but not limited to, rectangular, square, circular, ovoid, polygonal and elliptical. Hinge elements 15 may be located at an axis point of the reinforcing member 50 and may generally be provided as an opposing pair. The resulting finished package 20 may generally assume the overall shape of the reinforcing member 50 e.g., a circular reinforcing member 50 may yield a generally cylindrical package; an ovoid reinforcing member 50 may yield a tubular ovoid package, etc.

Further discussion of an exemplary flexible package may be found in U.S. patent application Ser. No. 10/971,636 filed in the name of Saggar et al. entitled Flexible Stable Easily Opened Package (P&G Case No. 9809).

Exemplary Package Pre-Form Chain

The production line 100 of the present invention corresponds to a continuous process of an in-line assembly of the package 20. FIG. 3 exemplifies that the flexible wall material 40 may be introduced into the production line 100 in such a manner as to form opposing side panels A and A′. This may be by folding the flexible wall material 40 into a U- or V-shaped formation as shown in FIG. 3. A composite structure 16 may exist after initial attachment of the flexible wall material 40 to a reinforcing member 50. The composite structure 16 may comprise the flexible wall material 40 in an unattached state outboard of the leading edge 51 and trailing edge 52 of the reinforcing member 50 of the composite structure 16. Opposing side panels B and B′ of the flexible wall material 40 may be situated between sequentially attached reinforcing members 50 which comprise composite structures 16. Creating package pre-form seals 34 in the flexible wall material 40 outboard of the reinforcing member 50 may convert the composite structure 16 into a package pre-form 17. The package pre-form seal 34 may comprise two longitudinal edges 31 and 32. Multiple package pre-forms 17 connected to each other may form a package pre-form chain 25 comprising a series of package pre-forms 17 linked together. Each of the package pre-forms 17 of the chain 25 may have a reinforcing member 50 in either a closed or open configuration. Opposing side panels C and C′ of the flexible wall material 40 may be situated between the package pre-form seals 34 and the reinforcing member 50 which together may comprise a package pre-form 17. The package pre-form seal 34 may be cut, at a location intermediate to the two longitudinal edges 31 and 32, to produce an end seal 30 of a package pre-form 17. Opposing side panels D and D′ of the flexible wall material 40 may be situated between the reinforcing member 50 and the end seal 30. The area of flexible wall material 40 characterized by D and D′ may generally be termed a flap 35.

Production Line

The production line 100 may be an in-line assembly of the package 20. The production line 100, depending on the complexity of the flexible package 20, can include any number of stations, wherein each station may provide either a particular component of the flexible package for attaching to the rest of the components into a final product or may manipulate the provided components to further manufacture the final package. In addition, the sequential order of the stations can vary depending upon the type of flexible package 20 being produced, its particular design, as well as many other processes and production considerations. Further, the production line 100 can be configured to form any suitable configuration of the stations on the production floor. The production line 100 may have a linear configuration of the stations, however, the configuration may also be curvilinear, circular, rectilinear, U-shape, C-shape, X-shape, cross-shape, or any combination thereof. Further, several production lines 100 can be situated in any suitable relation to each other to form any suitable arrangement on the production floor.

The production line 100 may comprise one or more stations, such as assembly stations, cutting stations, closing stations, opening stations, and gusseting stations. The stations may be placed in any order and some or all stations may be utilized for the production of a flexible package.

It may be desired to advance the package chain in a stepwise manner, bringing various portions of the package chain to appropriate workstations as exemplified below. It may be desired to produce a package of the present invention in the machine direction (MD). The machine direction may be the designated direction of flow of workpieces from the beginning of the process to the final product. It should be understood that any or all steps may be performed in the cross direction (CD). The cross direction may be designated as a direction perpendicular to the machine direction.

FIG. 4 depicts a schematic diagram of one embodiment of a composite structure 16 being processed into a package pre-form 17 and further processed in the production line 100 of the present invention to produce a flexible package 20 such as shown in FIG. 1. A reinforcing member 50 may be partially attached to the flexible wall material 40 forming a composite structure 16. The reinforcing member 50 may be in a sufficiently open configuration during attachment. The reinforcing member 50 may be positioned into a sufficiently closed configuration following the initial attachment of the flexible wall material 40 to the reinforcing member 50.

A package pre-form seal 34 may be cut (as discussed above) to produce a package pre-form 17 comprising at least one end seal 30. It has now been discovered that if the reinforcing member 50 was positioned in a sufficiently closed configuration, the reinforcing member 50 may be reopened to allow the flap 35 comprising the flexible wall material 40 and the end seal 30 to be naturally drawn into position for attachment of the flexible wall material 40 to the remainder of the reinforcing member 50 to transform the package pre-form 17 into a package 20. Without being bound by theory, this may be a natural result of an appropriately selected relationship between the overall size of the package 20 and the size of the reinforcing member 50.

FIG. 5 depicts a production line of an in-line assembly of a package 20. An assembly station 75 may receive both the flexible wall material 40 (such as from a continuous supply) and the reinforcing member 50 (as a series of discrete parts). The reinforcing member 50 may be positioned to accept the attachment of e portion of the flexible wall material 40 on portions of the reinforcing member 50 perimeter to produce a composite structure 16. Package pre-form seals 34 may then be formed outboard of the reinforcing member 50 to create a package pre-form 17. Multiple package pre-forms 17 may remain connected to form a package pre-form chain 25 (as shown in FIG. 3) or the package pre-form seals 34 may be cut at a location intermediate to the package pre-form seal edges, such as edges 31 and 32, to produce a cut edge 33 thereby further producing individual package pre-forms 17.

The reinforcing member 50 may be at least partially attached to the flexible wall material 40 in the assembly station 75. In the context of the present invention, the assembly station 75 may be provided with the ability to detect any loss of synchronization between the flexible wall material 40 and the reinforcing member 50. The detection means for detecting loss of synchronization may be implemented in a wide variety of ways. The detection means may be optical cells or mechanical feelers situated at a measured and known fixed distance from the points of attachment. The detection means may be adapted to ensure synchronization relative to detection marks applied to the flexible wall material 40 and/or the reinforcing member 50.

Providing a Flexible Wall Material

As may be seen in FIG. 5, a flexible wall material 40 may be provided in a substantially continuous manner (i.e., the flexible wall material may be supplied continuously during the normal operation of the process) such as from a bulk supply roll (not shown). Suitable flexible wall materials may include either a natural or synthetic material or any combination thereof, including films, film laminates, non-woven laminates, sponges, non-woven webs, woven webs, knitted fabrics, foams, natural materials, and any combination thereof, or dry lap materials including wood pulp, and the like, having a single layer or multiple layers and any combination thereof. Additional suitable flexible wall materials may be found as disclosed in U.S. Pat. Nos. 5,006,380, 5,205,650, 5,518,801, 5,650,214, 5,691,035, 5,723,087, 6,394,652. In some embodiments, the flexible wall material 40 may include a fibrous substrate such as an extensible non-woven web that comprises polyolefin fibers and/or filaments. In some embodiments, the flexible wall material 40 may have a peak load in grams-force (g_(f)) as measured under the Stiffness of Fabric Test of less than about 250 g_(f), or less than about 500 g_(f), or less than about 1000 g_(f). It will be appreciated, by those of skill in the art, that the Stiffness of Fabric Test can be employed on materials not commonly thought of as “fabrics” such as leather, synthetic leather, plastics, and other materials from which packages can be made.

The flexible wall material 40 may be provided by bulk supply roll or on-line formation. In such an embodiment, the process may be equipped with a formation station where the flexible wall material 40 may be created. Methods for creating a flexible wall material 40 such as, for example, films, knitted fabrics, woven fibrous webs, non-woven fibrous webs, laminates or combinations thereof are well known in the art.

As shown in FIG. 5, the flexible wall material 40 may be fed into a trough 55 to allow for a general U-shape of the flexible wall material 40 to form opposing panels 42 and 44 situated on either side of the reinforcing member 50. As previously stated, a single sheet of flexible wall material 40 may be fed into a trough 55 to form a continuous bottom wall 82. In another embodiment, multiple sheets of flexible wall material 40 may be fed into a trough 55. The distal ends of the sheets (not shown) may then be attached together to form a bottom wall 82. The uppermost portion of the trough 55 may comprise a guide track 60 for receiving items such as reinforcing members 50.

Providing Reinforcing Members

As may be seen in FIG. 5, a plurality of reinforcing members 50 may be provided in a substantially sequential manner (i.e., the reinforcing member may be supplied in a pattern of one reinforcing member following another reinforcing member at specified intervals during the normal operation of the process). In some embodiments, the reinforcing members 50 may be dropped onto a guide track 60 by a mandrel 65 (shown in FIG. 7). In other embodiments, the reinforcing member 50 may be placed into the track 60 from the same directional plane. The reinforcing member 50 may be provided to the production line 100 in such a manner as to have a leading edge 51, trailing edge 52, and two opposing side edges 53 and 54.

The reinforcing member 50 may be of any convenient and desired configuration. It may be useful to provide a reinforcing member 50 comprising a perimeter. It may also be useful to provide a reinforcing member 50 which provides a defined perimeter of the opening 70 of the package 20. The perimeter may be in the shape of a square, rectangle, circle, elliptical, polygon or oval configuration. The package 20 may be formed into the same perimeter shape of the reinforcing member, but the overall shape of the package 20 should not be so limited.

It may also be useful to provide the reinforcing member 50 with a pair of hinge elements 15. The hinge elements 15 may be located on the leading edge 51 and trailing edge 52 of the reinforcing member 50. Such a hinge element 15 could be an area of weakness, reduced diameter, or the like within the reinforcing member 50 providing a defined location where the reinforcing member 50 can bend about a folding axis. The hinge elements 15 can be actual hinge structures such as a pinned structure. The hinge elements 15 may also be so called “living hinges” in which joints are created by an area or zone of weakness in the reinforcing member 50 as a whole. The hinge elements 15 designed as “living hinges” are areas of less material and preferred bending and weakness designed to allow the reinforcing member 50 to be opened and closed multiple times throughout its life. It may be desired to design the reinforcing member 50 and the hinge elements 15 such that the reinforcing member tends to be stable in at least a closed and near full open position. Thus, it may be desired that when the reinforcing member 50 is in the open configuration (as shown in FIG. 1), it does not tend to close on its own in the absence of externally applied forces. This may allow the reinforcing member 50 to hold the opening 70 of the package 20 open for article retrieval and use.

The reinforcing member 50 may be composed of a variety of materials including, but not limited to, cardboard, corrugated paper, wood, metal, cardstock, thermoplastic material, non-thermoplastic material (i.e., plastic), paper, ceramic, bone, thermosetting polymers and combinations thereof. The reinforcing member 50 may be, but need not be, comprised of a thermoplastic material. For example, the reinforcing member 50 may be comprised of a high density polyethylene injection molded frame. The reinforcing member 50 may also be comprised of polypropylene, polyethylene, and combinations thereof. The reinforcing member 50 may be of a thickness sufficient to provide some degree of rigidity as compared with the flexible wall material 40. The materials of the reinforcing member 50 and the flexible wall material 40 may be the same or similar and may be selected to be compatible with the method of attachment utilized to attach the reinforcing member 50 to the flexible wall material 40.

Attaching the Flexible Wall Material to the Reinforcing Member

The flexible wall material 40 may be attached to at least a portion of the perimeter of the reinforcing member 50. As shown in FIG. 5, attachment of the flexible wall material 40 to the reinforcing member 50 may occur more than once during production. The term “attach” is not limited to securing the flexible wall material 40 to the entire perimeter of the reinforcing member 50. Rather, attachment may occur multiple times to various portions of the perimeter. The flexible wall material 40 may be partially attached to a first portion of the perimeter of the reinforcing member 50 in an assembly station 75. The first partial attachment of the flexible wall material 40 to a first portion of the perimeter of the reinforcing member 50 may occur in the machine direction. In another embodiment, the flexible wall material 40 may also be attached to the opposing side edges 53 and 54 of the reinforcing member 50. The composite structure 16 may then be in either a closed or open configuration. The flexible wall material 40 may be cut prior to any further attachment of the flexible wall material 40 to the reinforcing member 50.

Attachment of the flexible wall material 40 to the remainder of the perimeter may occur following the initial attachment or may occur prior to or following the opening and/or closing of the reinforcing member 50 and/or cutting of the flexible wall material 40. The attachment of the flexible wall material 40 to the remainder of the perimeter of the reinforcing member 50 may occur in the cross direction. In another embodiment, attachment of the remainder of the flexible wall material 40 may also occur to the leading edge 51 and trailing edge 52 of the reinforcing member 50.

As shown in FIG. 5, the flexible wall material 40 and the reinforcing member 50 may be brought together in a face-to-face relationship by way of bonding rolls 77. The bonding rolls 77 may form a bonding nip whereby the flexible wall material 40 and the reinforcing member 50 may be brought into contact and may be compressed. In the case of adhesive attachment, compression may improve adhesive spread and/or penetration into the flexible wall material 40 and/or the reinforcing member 50 thus providing for a stronger adhesive bond. In the case of thermo-mechanical bonding, the bonding rolls may impart bonding by heat and/or pressure so as to fuse the flexible wall material 40 and the reinforcing member 50.

Forming a Package Pre-Form Seal

As may be seen in FIG. 5, the flexible wall material 40 extending outboard of the reinforcing member 50 may be attached together to form a package pre-form seal 34.

If the attachment is performed by an adhesive applicator (not shown), the adhesive applicator may apply an effective amount of adhesive so as to attach the flexible wall material 40 together. The opposing flexible wall material panels 42 and 44 may be brought together in a face-to-face relationship by way of a profile sealer 37. The profile sealer 37 may form a package pre-form seal 34 whereby the opposing panels 42 and 44 may be brought into contact with each other and pressed together. In the case of an adhesive sealing, compression may improve adhesive spread and/or penetration into the flexible wall material 40 thus providing for a stronger adhesive bond. In the case of thermo-mechanical bonding, the profile sealer 37 may impart bonding by heat and/or pressure so as to fuse the flexible wall material 40.

The profile sealer 37 may include multiple seal bars 38 and supply heat in a conventional manner. The profile sealer 37 may supply the fusion energy necessary to adhere the flexible wall material 40 together. The seal bars 38 of the profile sealer 37 may be positioned on opposite sides of the production line and, when actuated, seal the flexible wall material 40 creating a package pre-form seal 34. The seal bars 38 may exert an external pressure along the longitudinal length of the flexible wall material 40 to form a package pre-form seal 34.

The package pre-form seals 34 may be formed at time intervals according to the overall size of the package 20. Optionally, the spacing between the package pre-form seals 34 may be varied according to specifications of the desired package 20. The package pre-form seal 34 may have two longitudinal edges 31 and 32 delineating the boundary of the package pre-form seal 34. The package pre-form seals 34 may have a generally constant width throughout the package pre-form seal 34.

Cutting Said Flexible Wall Material

As may be seen in FIG. 5, the package pre-form seals 34 of the flexible wall material 40 may be severed to create discrete segments of package pre-forms 17. Cutting may occur by various cutters, including but not limited to, knives and lasers. In one embodiment, a series of guillotine-type cutters (not shown) may be employed to sever the package pre-form chain 25 (as shown in FIG. 3) into package pre-forms 17. The cutters may be aligned so as to sever the package pre-form seals 34. Cutting of the package pre-form seal 34 may generally occur at a position intermediate to the two longitudinal edges 31 and 32 of the package pre-form seal 34. In another embodiment, two package pre-form seals 34 may be formed external to either the leading edge 51 or trailing edge 52 of the reinforcing member 50 prior to cutting the flexible wall material 40. In this embodiment, cutting may generally occur in the area of the unattached flexible wall material 40 situated between the two package pre-form seals 34.

In another embodiment, the cutting of the flexible wall material 40 may occur immediately following, or in conjunction with, the formation of the package pre-form seals 34. In this alternate embodiment, the cutters may be located within the profile sealer 37 and upon activation, the cutters may extend beyond the seal bars 38 to create the cuts which would separate the package pre-forms 17.

It may be desirable to support the segments of the package chain prior to the severing operation so as to maintain positional control of the severed flexible packages. Any of a number of conventional supports, such as vacuum operated suction cups can be employed for this purpose. If suction cups are utilized, they may be located on opposite sides of the flexible packages so that, by withdrawing the suction cups away from one another, the reinforcing member may be opened.

Opening the Reinforcing Member

As shown in FIG. 5, the reinforcing member 50 may be in an open configuration at any point in the production line 100. The reinforcing member 50 may be provided to the production line 100 in an open configuration. The reinforcing member 50 may also be placed into an open configuration at any point during production.

Opening of the reinforcing member 50 may be done in a variety of ways. The reinforcing member 50 may be formed by injection molding in an open configuration. The reinforcing member 50 may also be opened by mechanical means. Methods that may be used to open the reinforcing member 50 may include, but are not limited to, suction cups, pry bars, flat ploughs, tongs, magnetic force, air blasts, ploughs, and combinations thereof.

Closing the Reinforcing Member

As shown in FIG. 6, the reinforcing member 50 may be in a closed configuration at any point in the production line 100. The reinforcing member 50 may be provided to the production line 100 in a closed configuration. The reinforcing member 50 may also be placed into a closed configuration while moving through the production line 100, such as prior to reaching an assembly station 75. The reinforcing member 50 may also be placed into a closed configuration after passing through an assembly station 75 (as shown in FIG. 7).

Closure of the reinforcing member 50 may be conducted in a variety of ways. The reinforcing member 50 may be formed by injection molding in a closed configuration. The reinforcing member 50 may also be closed by any mechanical means such as closure bars 95 placed along the production line 100 or by magnetic force or air blasts and combinations thereof. FIG. 6 exemplifies that closure bars 95 may also be located along the topside of the production line 100 and placed into the hinge elements 15 of the reinforcing member 50 in order to close the reinforcing member 50 (also shown in FIG. 7). The reinforcing member 50 may also be closed by pressure exerted by the flexible wall material 40 following attachment.

Forming an Optional Bottom Gusset in the Flexible Wall Material

As shown in FIG. 7, it may be desirable to form a bottom upward fold in the flexible wall material 40 forming a gusset in order to facilitate the formation of a flat bottom 82 in the flexible package 20 (as shown in FIG. 1). The flexible wall material 40 may be fed into a trough 55 in the production line 100. The trough 55 may further comprise at least one folding board 90. The flexible wall material 40 may be passed through the trough 55 in such a manner as to follow the shape of the folding board 90 thus allowing the flexible wall material 40 to fold in an upward direction forming a gusset.

Test Method Stiffness of Fabric Test

The Stiffness of Fabric Test is run for purpose of the present specification is a modification of the Stiffness of Fabric Test by Circular bend as described in the ASTM D 4032-94. (hereby incorporated by reference). The Stiffness of Fabric Test for purposes of the present specification is conducted as follows:

Summary of Test Method

A pusher-ball forces a swatch of material through an orifice in a platform. The maximum force required to push the fabric through the orifice is an indication of the material's stiffness (resistance to bending).

Apparatus

-   Circular Bend Stiffness Tester, having the following parts: -   Platform, 102 by 102 by 6 mm smooth-polished chrome-plated steel     plate with a 38.1-mm diameter orifice. The lap edge of the orifice     should be at a 45° angle to a depth of 4.8 mm. -   Pusher-Ball, 6mm diameter steel spherical ball, mounted concentric     with orifice, 16 mm clearance on all sides. The bottom of the     pusher-ball plunger should be set at 3 mm above the top of the     orifice plate. From this position, the downward stroke length is 57     mm. -   Force-Measurement Gage, dial or digital type Dial gages with maximum     reading pointer in different capacities ranging from 1 to 50 lbf,     0.5 to 25 kgf, or 5 to 200 N with 100 graduations minimum; or     Digital gage with maximum reading “hold” feature and capacity of 100     lbf, 50 kgf, or 500 N, with 1000 graduations minimum. -   Actuator, manual or pneumatic. -   Specimen Marking Template, 102 by 102 mm. -   Stop Watch, for checking stroke speed.     Number and Preparation of Test Specimens

Using the specimen marking template specified above mark and cut five test specimens from staggered areas of each swatch of material to be tested. It will be appreciated that it may not be practical or possible to obtain all samples from a particular swatch (or particular product if the material is only available as incorporated into a product). In such a case, it is acceptable to take samples from multiple products or swatches. Samples with bonded, seals, seams or the like should be avoided. Lay each specimen flat to form a square 102 by 102 mm. Handling of specimens should be kept to a minimum and to the edges to avoid affecting stiffness properties.

Conditioning

Store the samples for 8 hours or more at 23° C and 50% relative humidity.

Procedure

-   Set the tester on a flat surface with dial at eye level. -   Select a gage with a capacity in which results will fall within 15     to 100 % of dial gage force or 1.5 to 100 % of digital gage force. -   Check tester pusher-ball speed control for full stroke length. -   Pneumatic Actuator—Set the air pressure control to the actuator at     324 kPa. Using a stop-watch, adjust the pneumatics to provide     plunger speed of 1.7±0.15 s under no load conditions. -   Manual Actuator—Using a stop-watch, establish and confirm a plunger     speed of 1.7±0.3 s. -   Center a specimen on the orifice platform below the pusher-ball. If     3.2 mm clearance under pusher-ball prevents ease of entry of     specimen due to sample thickness, the clearance may be increased to     6.3 mm maximum. In reporting, the results should indicate the     pusher-ball clearance, if not standard. -   Check the gage zero and adjust, if necessary. -   Set the maximum force reading switch. -   Actuate the pusher-ball for the full stroke length. Avoid touching     the specimen during testing. -   Record maximum force reading to nearest gage graduation. -   Continue as directed above until all specimens have been tested.     Calculation -   Average the individual specimen readings and round to the nearest     gage increment. -   Report -   Report the Average force in gage units.     End of Test

All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this written document conflicts with any meaning or definition of the term in a document incorporated by reference, the meaning or definition assigned to the term in this written document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. 

1. A method for manufacturing a flexible package, the method comprising the steps of: a) providing a continuous flexible wall material, b) providing a reinforcing member, said reinforcing member comprising a perimeter, c) attaching a first portion of said flexible wall material to a first portion of said perimeter of said reinforcing member, to provide a composite structure comprising an attached first portion and an unattached second portion, d) cutting said continuous flexible wall material to form a package pre-form, e) attaching a second portion of said flexible wall material to said unattached second portion.
 2. The method of claim 1 wherein said perimeter of said reinforcing member comprises a leading edge, a trailing edge, and opposed side edges.
 3. The method of claim 2 wherein said leading edge and said trailing edge comprise hinge elements.
 4. The method of claim 2 wherein said flexible wall material is first attached to said opposed side edges of said perimeter of said reinforcing member.
 5. The method of claim 4 wherein said flexible wall material is attached to said leading edge and said trailing edge of said perimeter of said reinforcing member subsequent to said first attachment.
 6. The method of claim 1 wherein said perimeter of said reinforcing member comprises a configuration selected from the group consisting of square, rectangle, circle, ellipse, polygon and oval.
 7. The method of claim 1 wherein attachment of said flexible wall material to said remaining portion of said perimeter of said reinforcing member occurs with said reinforcing member in a closed or a partially closed configuration.
 8. The method of claim 1 further comprising a step of forming a package pre-form seal outboard of said reinforcing member, wherein said package pre-form seal comprises opposed longitudinal side edges.
 9. The method of claim 8 wherein said package pre-form seal is cut at a position intermediate to said side edges of said package pre-form seal.
 10. A method for manufacturing a flexible package, the method comprising the steps of: a) providing a continuous flexible wall material, b) providing a reinforcing member comprising opposed side edges, a leading edge and a trailing edge opposed said leading edge wherein said leading edge and said trailing edge comprise hinge elements, c) attaching said flexible wall material to said opposed side edges of said reinforcing member to provide a composite structure, d) at least partially closing said reinforcing member, e) forming a package pre-form seal outboard of said reinforcing member, wherein said package pre-form seal comprises two opposed longitudinal side edges, f) cutting said package pre-form seal at a position intermediate to said side edges of said package pre-form seal to form a package pre-form, g) at least partially opening said reinforcing member, h) attaching said flexible wall material to said leading edge and said trailing edge of said reinforcing member.
 11. The method of claim 10 wherein said flexible wall material is provided into a trough wherein said trough comprises at least one folding board, wherein said folding board allows said flexible wall material to fold in an upward direction.
 12. The method of claim 10 wherein closure is achieved by a method selected from the group consisting of mechanical closure, closure bars, magnetic force, air blasts, external pressure, and combinations thereof.
 13. The method of claim 10 wherein opening is achieved by a method selected from the group consisting of suction cups, pry bars, flat ploughs, tongs, magnetic force, air blasts, ploughs, and combinations thereof.
 14. The method of claim 10 wherein said hinge elements comprise living hinges.
 15. The method of claim 10 wherein more than one said package pre-form seal is located outboard of at least one edge of said reinforcing member, wherein said flexible wall material is unbonded between said multiple package pre-form seals.
 16. The method of claim 15 wherein said cutting occurs at a position intermediate to said multiple package pre-form seals.
 17. An intermediate product in a continuous manufacturing process comprising: a) a continuous flexible wall material, b) a plurality of reinforcing members attached to said flexible wall material at spaced apart locations along said flexible wall material.
 18. The intermediate product of claim 17 wherein said continuous flexible wall material is partially attached to said reinforcing members.
 19. The intermediate product of claim 17 wherein said reinforcing members are in either an open or partially open configuration.
 20. The intermediate product of claim 17 wherein said reinforcing members are in a closed or partially closed configuration.
 21. The intermediate product of claim 17 comprising a package pre-form seal between said reinforcing members. 